[x264-devel] FFMpeg - x264

Denis info at denisgottardello.it
Tue Sep 13 12:22:03 CEST 2011



Like you can see below I have write a function for grab frames from webcam and 
for store these in a mpg file with h264.
I am sure that this function IS NOT CORRECT! I can see the video (if you want 
to try "www.denisgottardello.it/a.mpg") with mplayer but mplayer shows the 
video at 50 fps. The function has 25 fps instead.
Vlc does not work.
Wich is the error? I can not to find it. I can not understand wich is the right 
way for store a frame in a h264 file.
Can you help me? I'm disperate!



void QThCamera::run() {
    qDebug() << "QThCamera::run() start";
    QString fileName= "a.mpg";
    CvCapture *Capture= NULL;
    Capture= cvCreateCameraCapture(Index, Width, Height);
    if (!Capture) qDebug() << "Cannot open or initialize webcam!";
    else {
        if (ExternalFrame) cvNamedWindow("Frame", CV_WINDOW_AUTOSIZE);
        IplImage *frame= 0;
        CvFont font;
        cvInitFont(&font, CV_FONT_HERSHEY_SIMPLEX, 0.5f, 0.5f);

        AVOutputFormat *pOutputFormat;
        pOutputFormat= av_guess_format("h264", NULL, NULL);
        if (!pOutputFormat) {
            qDebug() << "Could not set output format, using MPEG.";
            pOutputFormat= av_guess_format("mp4", NULL, NULL);
        }
        if (!pOutputFormat) qDebug() << "Could not set output format.";
        else {
            AVFormatContext *pFormatCtx= avformat_alloc_context();
            if (!pFormatCtx) qDebug() << "avformat_alloc_context Error!";
            else {
                pFormatCtx->oformat= pOutputFormat;
                snprintf(pFormatCtx->filename, sizeof(pFormatCtx->filename), 
"%s", fileName.toStdString().c_str());
                AVStream *pVideoStream= av_new_stream(pFormatCtx,0);
                if (!pVideoStream) qDebug() << "av_new_stream Error!";
                else {
                    AVCodecContext *pCodecCtx= pVideoStream->codec;
                    pCodecCtx->codec_id= pOutputFormat->video_codec;
                    pCodecCtx->codec_type= AVMEDIA_TYPE_VIDEO;
                    pCodecCtx->bit_rate= 40000;
                    pCodecCtx->width= Width;
                    pCodecCtx->height= Height;
                    pCodecCtx->time_base.den= 25;
                    pCodecCtx->time_base.num= 1;
                    pCodecCtx->gop_size= 25;
                    pCodecCtx->pix_fmt= PIX_FMT_YUV420P;
                    avcodec_thread_init(pCodecCtx, 10);
                    if (pFormatCtx->oformat->flags & AVFMT_GLOBALHEADER) 
pCodecCtx->flags |= CODEC_FLAG_GLOBAL_HEADER;
                    if (av_set_parameters(pFormatCtx, NULL)< 0) qDebug() << 
"av_set_parameters Error!";
                    else {
                        dump_format(pFormatCtx, 0, 
fileName.toStdString().c_str(), 1);
                        AVCodec *pCodec= avcodec_find_encoder(pCodecCtx-
>codec_id);
                        if (!pCodec) qDebug() << "avcodec_find_encoder Error!";
                        else {
                            if (avcodec_open(pCodecCtx, pCodec)< 0) qDebug() 
<< "avcodec_open Error!";
                            else {
                                if (url_fopen(&pFormatCtx->pb, 
fileName.toStdString().c_str(), URL_WRONLY)< 0) qDebug() << "url_fopen Error!";
                                else {
                                    av_write_header(pFormatCtx);
                                    int BYTEPIC= Width * Height * 3;
                                    uint8_t *pOutBuffer= 
(uint8_t*)malloc(BYTEPIC); {
                                        int Frames= 0;
                                        QDateTime QDTStart= 
QDateTime::currentDateTime();
                                        while (DoStart) {
                                            if (!cvSetChannel(Capture, 
Channel)) qDebug() << "Unable to set channel.";
                                            frame= cvQueryFrame(Capture);
                                            if (frame) {
                                                if (MainForm->ui-
>QCBAutoBrightness->isChecked()) {
                                                    int Brightness= 
BrightnessOfAPixel(frame);
                                                    Brightness= ((Brightness * 
200 / 256) - 100) * -1;
                                                    IplImage *frame2= 
ContrastBrightness(frame, 0, Brightness); {
                                                        cvCopyImage(frame2, 
frame);
                                                    }{
                                                        cvReleaseImage(&frame2);
                                                    }
                                                } else {
                                                    IplImage *frame2= 
ContrastBrightness(frame, MainForm->ui->QHSContrast->value(), MainForm->ui-
>QHSBrightness->value()); {
                                                        cvCopyImage(frame2, 
frame);
                                                    }{
                                                        cvReleaseImage(&frame2);
                                                    }
                                                }
                                                if (MainForm->ui-
>QCBShowDateTime->isChecked()) cvPutText(frame, 
QDateTime::currentDateTime().toString("dd-MM-yyyy hh:mm:ss").toAscii(), 
cvPoint(10, 20), &font, cvScalar(255, 255, 255));
                                                if (MainForm->ui->QRBRotate90-
>isChecked()) {
                                                    IplImage *frame2= 
Rotate(frame, 90); {
                                                        cvCopyImage(frame2, 
frame);
                                                    }{
                                                        cvReleaseImage(&frame2);
                                                    }
                                                } else if (MainForm->ui-
>QRBRotate180->isChecked()) {
                                                    IplImage *frame2= 
Rotate(frame, 180); {
                                                        cvCopyImage(frame2, 
frame);
                                                    }{
                                                        cvReleaseImage(&frame2);
                                                    }
                                                } else if (MainForm->ui-
>QRBRotate270->isChecked()) {
                                                    IplImage *frame2= 
Rotate(frame, 270); {
                                                        cvCopyImage(frame2, 
frame);
                                                    }{
                                                        cvReleaseImage(&frame2);
                                                    }
                                                }
                                                if (ExternalFrame) 
cvShowImage("Frame", frame);
                                                QImage Image(frame->width, 
frame->height, QImage::Format_RGB888);
                                                const unsigned char *data= 
NULL;
                                                data= (unsigned char*)(frame-
>imageData);
                                                Image= QImage(data, frame-
>width, frame->height, frame->widthStep, QImage::Format_RGB888);
                                                if (DoStart) emit 
SendNewImage(Image);


                                                AVFrame *pAVFrame= 
avcodec_alloc_frame();
                                                uint8_t *pBuffer= 
(uint8_t*)malloc(avpicture_get_size(PIX_FMT_YUV420P, Width, Height)); {
                                                    avpicture_fill((AVPicture*)pAVFrame, 
pBuffer, PIX_FMT_YUV420P, Width, Height);
                                                    IplImageToAVFrame(frame, 
pAVFrame, Width, Height, PIX_FMT_YUV420P);
                                                    pAVFrame->pts= Frames;
                                                    int OutSize= 
avcodec_encode_video(pCodecCtx, pOutBuffer, BYTEPIC, pAVFrame);
                                                    if (OutSize> 0) {
                                                        AVPacket Packet;
                                                        av_init_packet(&Packet);
                                                        //pkt.pts= 
av_rescale_q(pCodecCtx->coded_frame->pts, pCodecCtx->time_base, pVideoStream-
>time_base);
                                                        //if (pCodecCtx-
>coded_frame->key_frame) pkt.flags |= AV_PKT_FLAG_KEY;
                                                        Packet.stream_index= 
pVideoStream->index;
                                                        Packet.data= 
pOutBuffer;
                                                        Packet.size= OutSize;
                                                        if 
(av_write_frame(pFormatCtx, &Packet)!= 0) qDebug() << "av_write_frame Error!";
                                                    }
                                                    Frames++;
                                                    if (Frames> pCodecCtx-
>time_base.den / pCodecCtx->time_base.num * 20) break;
                                                }{
                                                    av_free(pAVFrame);
                                                    free(pBuffer);
                                                }


                                            } else qDebug() << 
"QThCamera::run() frame= false";
                                        }
                                        qDebug() << Frames / 
QDTStart.secsTo(QDateTime::currentDateTime());
                                    }{
                                        free(pOutBuffer);
                                    }
                                    av_write_trailer(pFormatCtx);
                                    url_fclose(pFormatCtx->pb);
                                }
                                avcodec_close(pVideoStream->codec);
                            }
                        }
                        for (int count= 0; count< pFormatCtx->nb_streams; 
count++) {
                            av_freep(&pFormatCtx->streams[count]->codec);
                            av_freep(&pFormatCtx->streams[count]);
                        }
                    }
                }
                av_free(pFormatCtx);
            }
        }
        cvReleaseCapture(&Capture);
        if (ExternalFrame) cvDestroyWindow("Frame");
    }
    qDebug() << "QThCamera::run() stop";
}




-- 
www.denisgottardello.it
Skype: mrdebug
Videosurveillance and home automation! 
http://www.denisgottardello.it/DomusBoss/DomusBossIndice.php


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